Heretofore, annular wave springs have been utilized to urge seat rings into sealing engagement with an associated valve member, such as a ball or a gate. As shown in U.S. Pat. No. 2,548,128 to J. R. Snyder dated Apr. 10, 1951, and U.S. Pat. No. 3,387,815 to C. G. F. Richards dated June 11, 1968, annular undulated wave springs are illustrated to urge a seat member into sealing engagement with an associated ball valve member. However, the prior art does not show the use of a plurality of annular undulated wave springs about a seat ring which are held in an oriented relation to each other so that contiguous wave springs are staggered with respect to the nodes of the springs.